Trimming machine



Api-il 11", 1939. c. A* BROSNAN ET A1. 2,154,028

TRIMMING MACHINE Filed Dec. 20, 1957- 2 Sheets-Sheet l 4l 12 ze 22 V il; ae M1531 17 .i 4Z 3 +18' M 1 60A. l I 2 April l`1, 1939. c. A. BRosNAN ET AL TRIMMING MACHINE Filed DeC. 20, 1957 .cm l- Patented Apr. 11, 1939 UNITED STATES PATENT OFFICE Worcester, Mass.,

assignors to Worcester Pressed Aluminum Company,'worster` Mass a COI'Poration of Massachusetts y Application December 20, 1937, Serial No. A1841.767

14 Claims.

This invention relates to machines for trimming irregular edges at the `open ends of metal cans and boxes, such irregular edges being practically unavoidable when boxes are formed from sheet metal blanks by pressing or drawing operations. llihile our improved machine is adapted for trimming all kinds of metal boxes, it is particularly designed for trimming boxes of noncircular cross section, such as square or rectangular boxes, and said machine demonstrates important advantages when so used.

Itis the general object of our invention to provide a trimming machine which will quickly and easily trim off irregular edges at the open ends of metal boxes, and which will leave a smooth end, substantially 4without burrs.

`Our invention lfurther relates to arrangements and combinations of parts which will be hereinafter described and more particularly pointed out in the appended claims.

`A preferredform of the invention is shown in the drawings, in which Fig. 1 is a s ideuelevation of our improvedtrimming machine;

e Fig. 2 is a partial plan view,v partly in section and looking in the direction of the arrow 2 in Fig. 1;

l Fig. 3 is a partial end View, looking in thesdirection of the arrow in Fig. 1;

Fig. 4 is av partial plan view, looking in the direction of the arrow 4 in Fig. 1 and showing also a box on the mandrel, partly in section;

Fig. 5 isran enlarged end View of the cutter and die, looking in the direction of the arrow 5 in Fig. 4;

Fig. 6 is a fragmentary View showing the cooperating cutter and die in a different cutting relation;

Fig. '7 is a partial end View showing the operation of the scrap cutter;

8 is a partial plan view of the mandrel and associated parts A in spaced relation;

Fig. 9 is van end view of the scrap cutter, lookinghin the direction of the arrow 9 in Fig. 8;

Fig. l() is anelevation of the die which is assocated with the mandreLlooking in the direction o f the arrow IU in Fig. 8;

` Fig. 1v1 is asectional plan view of the mandrel and assembled associated parts; and

Fig. 12 is a perspective View of a box after the trimming operation has been performed thereon.

Referring to Fig. 1, we have shown our improved machine assembled on a table I5 supported by legs or framemembers i6. A cutter shaft I1 is mounted in bearingbrackets I8 and I9 on the table I5, and is aligned with a driving shaft 20, supportedin a bearing 2| and connected to the shaft I1 by a one-revolution clutch 22. This clutch may be of any usual type and is conveniently operatedby a foot lever 23 through a link 24. The shaft 2D`is continuously rotated in any convenient manner as by a pulley 25 and belt 26.

A cutter 30 (Figs. 2, 3 and 5) is mounted on a disc 3l and may be secured thereto by screws 33. A plate 34 is pivoted on `a pin 35 in the cutter 30 and may benswung to one side to give access to the screws A33. The disc 3l, cutter 3l] and plate 34 are all mounted on the front end of the cutter shaft I1 andare firmly secured to rotate therewith by a clamping screw 36 and a key 31 (Fig. 4).

A mandrel shaft 40 (Fig. 2) is mounted to rotate in the bearing bracket I8 and is driven from the cutter shaft l1 by a gear 4l and pinion 42 in a 2-,to-1ratio, so that the mandrel shaft 40 rotates twice for each Asingle revolution of the cutter shaft I1. l

A chip cutteru4 5,a die 46 and a mandrel 41 are assembled on the mandrel shaft 40, as shown in Fig. 11, and areA secured in assembled relation thereon by a clamping screw 48.

These parts as illustrated are for a box of squarecross section and with rounded corners, but it will .be understood that the mandrel and associated parts maybe made of any desired shape to fit any particular type and size of box to be trimmed.

The mandrel 41 is preferably provided with longitudinal grooves 49 (Figs. 3 and 4) which prevent the `trapping of air between the closed end of the box and the outer end of the mandrel, which mightbtherwise be troublesome, due to the sealing effect of the lubricant used on parts associated with the mandrel. l

The die 46 is a hardened steel plate and corresponds in outline to the cross section of the box to be trimmed, which box is a close sliding t over the mandrel. l

The chip cutter 45 is slightly smaller than the cutter 46 and is provided with sharp cutting members 50 at several of its corners, which cutting members closely vengageV a concentric portion 5l of the flanged disc 3| during the second or noncutting revolution of the mandrel.

The chip cutter 45 is keyed to the mandrel shaft 40, as indicated at 52 in Fig. 11, and is provided with a pin 53 (Fig. 8) extending through a hole 54 (Fig. 10) in the die 46 and into a hole 55 (Fig.4 8) Y in Vthe lmandrel k41. With this construction, the parts 45, 46 and 41 rotate together and are positively driven by the mandrel shaft 40. A chute 60 may be provided for conveying the scrap to a suitable receptacle.

Having described the -details of construction of our improved trimming machine, the method of operation thereof is as follows:-

A box B is slipped over the mandrel 41 and die 46 to the position shown in Fig. 4, such action being permitted by a recessed portion 62 (Fig. 5) in the cutter 30. When the parts are b-rought to rest by the operation of the one-revolution clutch, the recessed portion 62 is associated with the mandrel 41 in such manner that a box may be freely slipped on the mandrel.

After the box has been thus positioned, the foot lever 23 is depressed and the cutter shaft l'l makes one revolution, while the mandrel 41 and associated parts make two revolutions. During the rst revolution of the mandrel, the irregularly formed cutting edge 63 of the cutter 30 cooperates with the die 46 asv shown in Figs. 4, 5 and 6 to trim they waste metal or scrap 65 (Fig. 4) from the open end of the box.

It will be noted that the cutting edge 63 is so designed that the overlap between the edge 63 and the edge of the die 46 is substantially constant, regardless of the non-circular section of the die 46. A uniform cutting action thus takes place entirely around the'box B, the scrap 65 being severed from the box'asA indicated in Fig. 4, and the end of the box being left with a smooth trimmed edge substantially devoid of burrs.'

Having severed the ring of scrap 65 from the end of the box B, it is obvious that the scrap ring must be removed before another box can be placed on the mandrel. For this purpose we provide the scrap cutter 45, which cooperates as indicated in Fig. 'l with the concentric flange 5l of the disc 3| during the second or non-cutting revolution of the mandrel shaft 40. During this second revolution, the three sharp edge members 50 of the scrap cutter-45 engage the concentric flange 5I and sever the scrap ring 65 at three successive points. The severed -pieces of scrap then fall freely to the chute 60 by which they are conveyed away.

Having completed the second revolution of the mandrel shaft 40, the machine is brought to rest by the automatic action of the one-revolution clutch 22, whereupon the trimmed box may be removed and an untrimmed box substituted therefor. The entire trimming and scrap-disposal operation is thus quickly and easily performed and the ends of the trimmed boxes are smoooth and uniformand in condition for immediate use.

Our improved machine is particularly adapted for trimming boxes pressed or drawn from aluminum or other relativelyductile metal, such as the boxes used to cover the tubesin radio apparatus.

While we have shown our machine as adapted to trim boxes of square cross section and with rounded corners, it will be obvious that boxes of other cross sections, such as square, triangular, rectangular or hexagonal, as well as oval or elliptical, may be trimmed with equal facility by providing mandrels and associated parts to lit the different boxes, and by providing cutters 30 of such outline as to maintain substantially uniform overlap with the die which fits the box to be trimmed.

Having thus described our invention and the advantages thereof, we do not wish to be limited to the details herein disclosed, otherwise than as set forth in the claims, but what Wev claim is:

1. A machine for trimming boxes of non-circular cross section comprising a die closely tting the interior of the box to be trimmed, a cutter co-acting with said die, said cutter and die being mounted to rotate on fixed parallel axes and said cutter being shaped to maintain substantially uniform box-trimming overlap therewith, and means to cause said die to rotate through a definite number of complete revolu tions for each revolution of said cutter, whereby the same parts of said cutter and die coact during each revolution of said cutter.

2. A machine for trimming boxes of non-circular cross section comprising a mandrel and die mounted to rotate together on a i'lxed axis, said die closely fitting the interior of the box to be trimmed, a cutter mounted to rotate about a xed parallel axis and having a non-circular cutting edge complementary to the edge of said die, and means to rotate said cutter and said die and mandrel in predetermined speed relation suoli that complementary parts of said cutter and die coact during every revolution of said cutter.

3. A machine for trimming boxes of non-circular cross section comprising a cutter and a die rotatab-le about fixed parallel axes, a mandrel rotatable with said die, said die closely tting the interior of the box to be trimmed, and means to give said die and mandrel two complete revolutions for each revolution of said cutter, whereby the same parts of said cutter and die always coact to trim the box, and the cutting edge of said cutter being shaped to maintain substantially uniform box-trimming overlap with said die in every cutting relation of said parts.

4. A machine for trimming boxes comprising means to give a box two successive revolutions, means to trim a continuous scrap ring from the open end of the box during the first revolution,

and means rotatable with the box and effective l `to cut said scrap ring into segmental fragments during the second revolution of the box.

5. A machine for trimming boxes comprising a rotatable mandrel and die to support the box, a rotating cutter coacting with said die to trim a continuous scrap ring from the open end of the box as the mandrel and cutter rotate, and means rotatable with said die and mandrel and effective to cut said ring into segmental fragments on further rotation of said cutter, mandrel and die.

6. A machine for trimming boxes comprising means to give the box two successive revolutions, means to trim a scrap ring from the open end of the box during the first revolution, and means to out said scrap ring into segmental fragments during the second revolution, said latter means coacting with a non-cutting surface of an element rotating with said scrap severing means.

'7. A machine for trimming boxes of non-circular cross section comprising a cutter and a die rotatable about xed parallel axes, a mandrel rotatable with said die, said die and mandrel closely fitting the interior of the box to be trimmed, and means to give said die and mandrel two complete revolutions for each revolution of said cutter, said box being trimmed during the first revolution of said die and mandrel, and means being provided to subdivide the scrap ring severed during the rst revolution into a plurality of segmental fragments during the second revolution of said die and mandrel.

8. A machine for trimming boxes of non-c-ircular cross section comprising a box-supporting mandrel, means to give said mandrel two Successive and complete revolutions only, means to trim the box on said mandrel during the rst revolution, and means to cut the severed scrap ring into segmental fragments during the second revolution.

9. A machine for trimming boxes of non-circular cross section comprising a box-supporting mandrel, means to give said mandrel two successive and complete revolutions, means to trim the box on said mandrel during the first revolution, means to cut the severed scrap ring into segmental fragments during the second revolution, and means to stop the machine on the completion of the second revolution.

10. A machine for trimming boxes of non-circular cross section comprising a box-supporting mandrel, means to give said mandrel two successive and complete revolutions only, means to trim the box on said mandrel during the rst revolution, and means to cut the severed scrap ring into segmental fragments during the second revolution, said trimming means comprising a die fitting the interior of the box to be trimmed and a cutter having a non-circular cutting edge complementary to said die and maintaining substantially uniform box-trimming overlap therewith.

11. A machine for trimming boxes of non-cir.- cular cross section comprising a box-supporting mandrel, means to give said mandrel two successive and complete revolutions only, means to trim the box on said mandrel during the rst revolution, and means to cut the severed scrap ring into segmental fragments during the second revolution, said trimming means comprising a die fitting the interior of the box to be trimmed and a cutter having a non-circular cutting edge complementary to said die and maintaining substantially uniform box-trimming overlap therewith. i

12. A machine for trimming boxes of non-circular cross section comprising a mandrel, a die and a scrap cutter all mounted to rotate together about a xed axis and said die closely fitting the interior of the box to be trimmed, a cutter mounted to rotate about a xed parallel axis and having a non-circular cutting edge complementary to the edge of said die, and means to rotate said cutter and said die, mandrel and scrap cutter in predetermined speed relation, such that complementary parts of said cutter and die coact during every revolution of said cutter, and

said cutter having an associated concentric element rotating therewith and coacting with said scrap cutter on every alternate revolution of said scrap cutter.

13. Apparatus to subdivide scrap rings trimmed from the open ends of metal boxes comprising a rotatable scrap cutter around which said ring is deposited as trimmed from the box, said cutter having circumferentially spaced cutting elements thereon, and a member rotating about an axis parallel to the axis of said scrap cutter and having a surface coacting with said cutting elements to out the scrap ring into segmental fragments.

14. Apparatus to subdivide scrap rings trimmed from the open ends of non-circular metal boxes comprising a polyangular rotatable scrap cutter around which said ring is deposited as trimmed from said box, said cutter having cutting elements at a plurality of corners thereof, and a member rotating about an axis parallel to the axis of said scrap cutter and having a surface coacting with said cutting elements to cut the scrap ring into segmental fragments.

CORNELIUS A. BROSNAN. PATRICK F. KELLEHER. 

